Chick cochlear hair cell exocytosis mediated by dihydropyridine-sensitive calcium channels.

J Physiol

Department of Clinical Studies-New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19348, USA.

Published: September 2001

1. A semi-intact preparation of the chick basilar papilla was developed to study calcium-dependent neurotransmitter release by tall hair cells (avian equivalent of cochlear inner hair cells). 2. Tall hair cell depolarization resulted in changes in cell membrane capacitance (DeltaC(m)) that reflected cell surface area increases following synaptic vesicle exocytosis and provided a surrogate measure of neurotransmitter release. Both calcium current (I(Ca)) and DeltaC(m) were reversibly blocked by cobalt, and exhibited a similar bell-shaped dependency on voltage with a peak response around -10 mV. 3. Pharmacological agents selective for L-type calcium channels were employed to assess the role of this channel type in neurotransmitter exocytosis. Nimodipine, a dihydropyridine (DHP) antagonist, suppressed I(Ca) and blocked DeltaC(m). Conversely, the DHP agonist Bay K 8644 increased both I(Ca) and DeltaC(m) amplitude nearly 3-fold. These findings suggest that chick tall hair cell neurotransmitter release is mediated by calcium influx through L-type calcium channels.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2278818PMC
http://dx.doi.org/10.1111/j.1469-7793.2001.00689.xDOI Listing

Publication Analysis

Top Keywords

hair cell
12
calcium channels
12
neurotransmitter release
12
tall hair
12
hair cells
8
ica deltacm
8
l-type calcium
8
hair
5
cell
5
calcium
5

Similar Publications

The sense of hearing originates in the cochlea, which detects sounds across dynamic sensory environments. Like other peripheral organs, the cochlea is subjected to environmental insults, including loud, damage-inducing sounds. In response to internal and external stimuli, the central nervous system directly modulates cochlear function through olivocochlear neurons (OCNs), which are located in the brainstem and innervate the cochlear sensory epithelium.

View Article and Find Full Text PDF

Moracin M promotes hair regeneration through activation of the WNT/β-catenin pathway and angiogenesis.

Arch Dermatol Res

January 2025

Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 54538, South Korea.

Hair follicle growth depends on the intricate interaction of cells within the follicle and its vascular supply. Current FDA-approved treatments like minoxidil have limitations, including side effects and the need for continuous use. Moracin M, a compound from Moraceae family, was investigated for its effects on hair growth and vascular regeneration.

View Article and Find Full Text PDF

Screening of Anti-Hair Loss Plant Raw Materials Based on Reverse Network Pharmacology and Experimental Validation.

Curr Issues Mol Biol

January 2025

Beijing Key Laboratory of Plant Resources Research and Development, School of Light Industry Science and Engineering, Beijing Technology and Business University, Beijing 100048, China.

Hair loss is one of the skin conditions that can affect people's mental health. Plant raw material extracts are of great interest due to their safety. In this study, we utilize reverse network pharmacology to screen for key targets of the Wnt/β-catenin signaling pathway and the TGFβ/BMP signaling pathway, as well as key differential lipids, for plant raw materials selection.

View Article and Find Full Text PDF

Objective: This research investigated the possible shielding properties of BB (Berberrubine) against the harmful auditory effects of cisplatin, preliminarily delving into the underlying mechanisms responsible for this protection.

Methods: HEI-OC1 cell viability was determined using a Cell Counting Kit-8 (CCK-8). The impact of BB on cochlear hair cells was studied through cochlear explants culture.

View Article and Find Full Text PDF

Extent of genetic and epigenetic factor reprogramming via a single viral vector construct in deaf adult mice.

Hear Res

December 2024

Bionics Institute, East Melbourne, Victoria 3002, Australia; Department of Medical Bionics, The University of Melbourne, Fitzroy, Victoria 3065, Australia; Department of Surgery (Otolaryngology), University of Melbourne, The Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria 3002, Australia. Electronic address:

In the adult mammalian cochlea, hair cell loss is irreversible and causes deafness. The basic helix-loop transcription factor Atoh1 is essential for normal hair cell development in the embryonic ear. Over-expression of Atoh1 in the adult cochlea by gene therapy can convert supporting cells (cells that underlie hair cells) into a hair cell lineage.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!